There have been a plurality of a type of a power supply circuit to be mounted in an electric equipment body such as an image forming apparatus, and such as, for example, a control parameter for controlling each power supply circuit is different depending on its type. The type therefore needs to be identified in the side of the electric equipment body. Considering the foregoing, there has conventionally been the electric equipment which is constituted in such a manner that an output from the power supply circuit is in a high or a low level state in accordance with the type, and on the other hand, the body of the electric equipment comprises a type identification port to which electric equipments of each type are connected and a main substrate, wherein the main substrate is constituted so as to conduct mode identification on the basis of the high and low state of the type identification port.
However, according to the conventional electric equipment, it has been necessary to separately provide a port for the type identification for power supply circuit.